Some integrated circuits have multiple circuit blocks that operate at different frequencies and voltages from one another. The different frequencies and voltages allow the frequency and voltage of each circuit block to be optimized for that circuit block. The circuit blocks are often powered by dynamic voltage and frequency scaling (DVFS) in which the frequency of operation and voltage of operation of the circuit block is continuously modified to suit the current operations performed by the circuit block. To supply the voltages to the various circuit block a separate voltage regulator module (VRM) corresponding to each circuit block is usually used.